The Major Deegan Expressway, officially named the Major William Francis Deegan Expressway and locally known as the Deegan, is a north–south expressway in the New York City borough of the Bronx. It is the southernmost 8.70 miles (14.00 km) of Interstate 87 (I-87), beginning at I-278 at the interchange of the Bruckner Expressway and the Triborough Bridge in the south Bronx and ending at the Westchester County line in Yonkers, where the New York State Thruway begins.